Apparatus for determining the angular position of an object



' I/VVE/VTOR COR/V51. IS 604007 aa wm-m 14 TTORWEKS July 20 1926. I

' C. SCHOUTE APPARATUS FOR DETERMINING THE ANGULAR POSITION OF AN OBJECT Filed March 28. 1923 Patented July 20, 1926. i i .4 1

UNITE :rra harass FICE.

connnnrs sonoutrn, or DE BILT, NETHERLANDS.

APPARATUS FOR DETERMINING THE ANGULAR POSITION OF AN OBJECT.

Application filed March 28, 1923, Serial No. 628,261, and in Germany October 16, 1922. r

- My present invention relates to apparatus so that the rolling of the vessel does practifor determining variable angles, comprising cally not interfere with the indications of a pair of interoommunicating vessels such the apparatus, a pitching movement of the as tubes movable'as a Whole about an axis vessel through angular distances of 6 up and and partially filled with an electrically condown does not cause a difference in the in- 60 ducting fluid, a conducting body arranged dication of the rudder position of fully 1 in one or in both of said vessels length from the correct value when both sets of wise therein, and means for determim tubes swing through equal angles in opposed. ing the electric resi tanc of the ndirections. In practice this slight difference" ducting body at varying angles of the may e neglected. 6 apparatus, reference being had to my My novel apparatus is of value not only British Pat nt No, 161,555, A paratus of for vessels, but also for aerial navigation, thischaracter serve to indicate through elec- Generally speaking it may be used whenever trio ans on distant i str t th riaitis desired to read variable positions of'a tion of the free length and, consequently, of p rt relative to a moving object. the electric resistance of the said conducting Referring to the drawing, Figure 1 shows body upon a swinging motion of the said the diagram, and F igure2 the construction 'gvessels owing to a dis la t r t an of an embodiment of the invention. angular movement of the object with which Referring to Figures 1 and12, he ub s 1, the said vessels are operatively coupled, 2 Of the one set and the tubes 1', 2' Of the The displacements or angular movements other set are interconnected through tubes of the object under consideration must, of 3 and respectively, of relatively ll course, be indicated relative to another ob- Cross-sectional area. The said sets of tubes ject which, in order that the apparatus may, e mounted on circular i c e and eoperate satisfactorily,should have no move sp c iv y, rotatable about shafts 5 and 5 inent with respect to the earth, in view of respectively. Longitudinally disposed in the fact that the operation of the apparatus the tubes 1, 2, 1 and 2 are conducting depends upon the horizontality of the surbodies or filaments 6,7,6 and 7 respectiveface of the conducting fluid in the intercomly. Said conducting bodies or filaments Inunicating vessels. For instance, in order form parts of two circuits as shown, which that the apparatus may be used for indioatcircuits comprise a common source of elecing on distant instruments the angular positricity 8 and a common resistance .9, and tion of a rudder, it is necessary for the apare connected to a common galvanometer, paratus to be supported in a gimbal and for 10 so as toform what may be called a lVheat- 35 the movements of the rudder to be transstone bridge. The discs 4 and 1 intermesh ,mitted thereto through flexible means, such by circular gear rims 11 and 11 respectively as a Bowden wire. Y 4 in such a manner that rotation of theone My present invention has for its principal disc a given direction causes the other object an improved arrangement whereby disc toturn through the same angular disthe gimbal may be dispensed with, so that tance'in the opposite direction. it is no longer necessary for the apparatus As shown in Figure 2 the sets 01. tubes 1, 2, to remain in an invariable position relative 3 and 1, 2, 3 are mounted on mitre wheels to the earth. Owing to this novel arrange 12 and 12 respectively, having equal diamment the apparatus may be rigidly secured eters and being keyed on shafts 5 and 5', to a ship and nevertheless accurately indicate respectively. The mitre wheels 12, 12 inthe angular position of the rudder notwithtermesh with a common mitre wheel 13 standing the motions of the ship in a seaway. keyed on a shaft 14C and driven through With said object in view the set of intersuitable gearing by a mitre wheel 15 in mesh communicating vessels or tubes is duplicated with a toothed quadrant 16. The quadrant and'both sets are so associated that opposed 16 is secured through arms 17 to the post movements are imparted thereto whenever 18 of a rudder 19. the object under consideration is displaced It is obvious that angular displacements or performs an angular movement. Calcu of the rudder 19 cause the two sets of tubes lation has shown that when the swingingv to swing in opposite directions through equal 5 axes of said sets are disposed athwartships angles, and that the positions of the rudder may be indicated at a distance through the above described electric means with quite sufficient accuracy.

It will be understood that when the rudder is in its neutral position the tubes will extend vertically, and the electrical resistance in each. branch of the Wheatstone bridge will preferably be equal, so that there will be no deflection of the galvanometer. When the rudder is moved to either side of neutral each set of tubes will. be proportionately inclined in opposite directions so that a proportionate variation of the liquid levels in all the tubes occurs, thereby producing variations, proportional to the movement of the rudder, in the electrical resistances of the conductors which form each of the arms or branches of the VVheatstone bridge circuit. As aresult of these variations in the electrical resistances there will occur, in accordance with the well known properties of the VVheatstone bridge circuit, a. deflection of the galvanometer which is accurately indicative of the direction and extent of the rudder movement. With an arrangement such as shown in Fig. 2', a rolling of the vessel would be equivalentto inclining the tubes shown in Fig. l at right angles to the plane of the paper. This obviously would cause only an inclination of the top surface of the liquid in, each tube, which inclination would be the same in each tube and therefore would not produce any differences in the electrical resistances of the branches.

A pitching of the vessel would produce an equal movement of the liquid longitudinally of the tubes, but in the same direction in each set of tubes. For example, if the pitching occurs, referring to Fig. 1, in a direction equivalent to a rotation of the paper in a clockwise direction, the liquid level will fall an equal amount in tubes 2 and 2 and will rise an equal amount in tubes 1 and 1. Taking the simplest case, that is with the rudder in neutral position, and assuming that 1' indicates the resistance of the wire for each branch of the circuit, n the distance the liquid level has varied in each tube, and that the branches 1*, r, r and r of the the condition for no current through the galvanometer, is fulfilled by the equation 1- n r n When the rudder is at an angle a, with current passing through the galvanometer, and a pitching of the vessel occurs, the inclination of the vessel causes a variation in the liquid levels of the tubes of one set equivalent to increasing, and in the other set to decreasing the angle 0., because of the fact that each set of tubes has been moved, in accordance with my invention, in opposite directions. Therefore the departure in the galvanometer indications from true rudder positions, caused by the pitching of the vessel when the rudder is inclined is, as can be readily proved by use of the mathematical formulae for the lVheatstone bridge, practically negligible, (not greater than 1%) even for tilting angles as high as 6.

hat I claim is In apparatus for determining variable angles, two sets of intercommunicating vessels partially filled with an electrically conducting fluid, a resistance body arranged in a vessel of each set in position to be affected by the level of the fluid, axes on each of which one of said sets is movable as a whole, connecting means between said sets to cause a swinging motion of the one set in one direction to impart swinging motion in the opposite direction to the other set, and indicating means responsive to variations in the electric resistance of said resistance bodies.

In testimony whereof I affix my signature.

DR. CORNELIS SCHOUTE. 

